1. Field of the Invention
This invention relates to polymeric hose and in particular to an apparatus for and method of curing such hose.
2. Prior Art Statement
It is known in the art to vulcanize or cure predetermined lengths of polymeric hose while confining the exterior surface of each hose length in a lead sheath and wherein at the end of the curing cycle the lead sheath is stripped from the cured hose and the lead reused; and, this basic process is widely used and referred to as the "lead press" method.
It has also been disclosed in U.S. Pat. No. 3,690,796 to provide continuous vulcanizing of a lead-sheath covered hose by moving such hose through a heating oven for vulcanizing purposes whereupon the lead sheath is continuously stripped from the hose as it leaves the oven.
Each of the above-described processes using lead is comparatively expensive due to the added operations made necessary because of the use of a lead sheath plus the substantial scrapping of hose lengths required because of damage often resulting upon removal of the lead sheath. In addition, special safety precautions must be taken when using lead in this manner.
It is also known to vulcanize reinforced elastomeric hose by immersing such hose in a bath of liquid such as water and disposing the hose and liquid bath in a pressurized heating environment, such as a steam filled vulcanizer, and such technique is disclosed in U.S. Pat. No. 3,824,141. This process may be practiced with the hose either filled with water or empty.
It is also known, as disclosed in U.S. Pat. No. 3,972,757, to build a hose which is to be vulcanized on a solid mandrel whereupon the hose and its mandrel are immersed in a bath of liquid and heated to thereby subject the hose wall to forces exerted in opposite directions by the heated liquid bath and the expanding mandrel.